Work plan

  1. write up some stuff I need to know about MDV surface moisture and its behaviour in this RMD as input to the paper

  2. explore soil moisture dataset

    • data cleaning necessary?
    • understand surface moisture and temperature information distributions, determine cut-off value (0°C? -x°C?)
    • spatial configuration of loggers, i.e. think about validation strategy (how to do the spatial CV)

  3. data gathering for pre-study: find a cloud free day and get as many useful spatial predictor datasets as possible

  4. describe and understand relations between surface moisture and predictors & temperature

    • surface moisture and elevation
    • surface moisture and temperature

  5. build model for case study

  6. run workflow for the whole temporal and spatial setting

To do’s:

  • ask Pierre about salinity and pH-paper progress

Paper relevant info

Introduction

Research Question:

  • For Method 1 and 2: How accuarate can surface moisture be modeled for the open soil areas within the Antarctic Dry Valleys?

  • actually interesting question: Which factors does the spatio-temporal surface moisture configuration in the MDV depend upon?

What we know about surface moisture in the MDV

and how to translate it into the approach

  • very low overall
  • longer wavelenghts can pick it up Predictor: SWIR
  • short duration of hydrological events

Soil Moisture generally

Soil Moisture MDV

  • soil moisture content important factor of thermal soil properties in the MDV, locations of most active heat-exchange are wetter soils with deeper active layers. Where there is less moisture, active layers are more shallow (most part in the MDV) (Ikard et al. 2009) Valley bottom soils very low SWC, 1% water volume in upper 3cm (Campbell et al. 1998)
  • proximity to hydrologic reservoirs spatial control on soil moisture (Wlostowski, Gooseff, and Adams 2018)
    • snow patches
    • streams
    • lakes
  • spatially discrete “wet patches” appear darker (Wlostowski, Gooseff, and Adams 2018), mechanisms for their formation: Predictor: optical satellite info
    • deliquescence (direct condensation of atmospheric water vapor into saline surficial soil pore spaces) (Joseph S. Levy et al. 2012)
    • subsurface routing of meltwater through water tracks (J. S. Levy et al. 2011), coincident with regions of high topographic flow accumulation Predictor: TWI
  • wet patch location (Langford, Gooseff, and Lampkin 2015): topography, regional microclimate influence their distribution Predictor: find a way to incorporate information on small depressions (1m DEM)
  • soil moisture controls freezing dynamics: based on field observations from sites with natural moisture gradients (active layer monitoring stations: temperature, soil moisture, pore water specific conductance along natural moisture gradient) and a numerical model, magnitude and trend of freezing rates as a function of soil moisture was captured: Soil moisture is a central control of freeze-thaw dynamics of active layer soils in the MDV “..a warmer and more variable climate will … exacerbate freeze-thaw cycling in the driest portions of the landscape.” Freezing events happen mosty in distal soils, i.e. where there is less soil moisture, low water content leads to more active layer freezing events, 0.08 m³/m³ seems to be the defining threshold, whether there will be much or little freezing events (Wlostowski, Gooseff, and Adams 2018)

MDV future climate

MDV ecosystems

  • MDV ecosystems “strongly controlled by abiotic habitat variables” (Wlostowski, Gooseff, and Adams 2018)
  • “Nematodes are the most abundant invertebrates found in the Dry Valleys soils and occupy the highest trophic level of a relatively simple soil food chain” (Cary et al. 2010). “Future changes in soil moisture will alter active layer freezing dynamics, possible eliciting shifts in nematode species diversity and abundance” (Wlostowski, Gooseff, and Adams 2018)

Questions

  • should I only use values above 0 degrees? Find out when water freezes in the MDV and how the relation to salinity would be

  • How does RH relate to soil moisture?

Data

Calibration and validation

AWS and iButton spatial distribution

Already available:

  • iButton data

To download:

Example: Explorer’s Cove

There is:

  • Air Temperature
  • Precipitation
  • Solar Radiation
  • Relative Humidity (that’s what iButtons measure)
  • Soil Moisture
  • Soil Temperature
  • Wind Direction and Speed

Potential spatial predictors

Potential spatial predictors

Already available:

  • DEM 8 / 30m * TWI * slope
  • rock outcrop to use as a mask
    • use soil type map to find out where there is only rock and no soil
  • LST 30m
  • soil types
  • pH model (Pierre: “pH is very much correlated to soil moisture, and more linear than EC (because it’s already a log scale!), but I could also share EC estimates if need be.”)

To acquire

  • RS data:
    • SWIR
    • downscaled LST
    • radar
  • EC (Pierre)?

Methods

Method schematic overview

Discussion

References

Anderson, D. M., and A. R. Tice. 1973. “The Unfrozen Interfacial Phase in Frozen Soil Water Systems.” In Physical Aspects of Soil Water and Salts in Ecosystems, edited by J. Jacobs, O. L. Lange, J. S. Olson, W. Wieser, A. Hadas, D. Swartzendruber, P. E. Rijtema, M. Fuchs, and B. Yaron, 4:107–24. Ecological Studies. Berlin, Heidelberg: Springer Berlin Heidelberg. https://doi.org/10.1007/978-3-642-65523-4{\textunderscore }12.
Campbell, Iain B., Graeme G. C. Claridge, David I. Campbell, and Megan R. Balks. 1998. “The Soil Environment of the Mcmurdo Dry Valleys, Antarctica.” In Ecosystem Dynamics in a Polar Desert, edited by John Charles Priscu, 297–322. Antarctic Research Series 0066-4634. Washington, D.C: American Geophysical Union. https://doi.org/10.1029/AR072p0297.
Cary, S. Craig, Ian R. McDonald, John E. Barrett, and Don A. Cowan. 2010. “On the Rocks: The Microbiology of Antarctic Dry Valley Soils.” Nature Reviews. Microbiology 8 (2): 129–38. https://doi.org/10.1038/nrmicro2281.
Chapman, William L., and John E. Walsh. 2007. “A Synthesis of Antarctic Temperatures.” Journal of Climate 20 (16): 4096–4117. https://doi.org/10.1175/JCLI4236.1.
Farouki, Omar T. 1981. “The Thermal Properties of Soils in Cold Regions.” Cold Regions Science and Technology 5 (1): 67–75. https://doi.org/10.1016/0165-232X(81)90041-0.
Fountain, Andrew G., Joseph S. Levy, Michael N. Gooseff, and David van Horn. 2014. “The McMurdo Dry Valleys: A Landscape on the Threshold of Change.” Geomorphology 225: 25–35. https://doi.org/10.1016/j.geomorph.2014.03.044.
Gooseff, Michael N., J. E. Barrett, Peter T. Doran, Andrew G. Fountain, W. Berry Lyons, Andrew N. Parsons, Dorota L. Porazinska, Ross A. Virginia, and Diana H. Wall. 2003. “Snow-Patch Influence on Soil Biogeochemical Processes and Invertebrate Distribution in the McMurdo Dry Valleys, Antarctica.” Arctic, Antarctic, and Alpine Research 35 (1): 91–99. https://doi.org/10.1657/1523-0430(2003)035[0091:SPIOSB]2.0.CO;2.
Gooseff, Michael N., John E. Barrett, Melissa L. Northcott, D. Brad Bate, Kenneth R. Hill, Lydia H. Zeglin, Michael Bobb, and Cristina D. Takacs–Vesbach. 2007. “Controls on the Spatial Dimensions of Wetted Hydrologic Margins of Two Antarctic Lakes.” Vadose Zone Journal 6 (4): 841–48. https://doi.org/10.2136/vzj2006.0161.
Ikard, Scott J., Michael N. Gooseff, John E. Barrett, and Cristina Takacs-Vesbach. 2009. “Thermal Characterisation of Active Layer Across a Soil Moisture Gradient in the McMurdo Dry Valleys, Antarctica.” Permafrost and Periglacial Processes 20 (1): 27–39. https://doi.org/10.1002/ppp.634.
Langford, Zachary L., Michael N. Gooseff, and Derrick J. Lampkin. 2015. “Spatiotemporal Dynamics of Wetted Soils Across a Polar Desert Landscape.” Antarctic Science 27 (2): 197–209. https://doi.org/10.1017/S0954102014000601.
Levy, J. S., A. G. Fountain, M. N. Gooseff, K. A. Welch, and W. B. Lyons. 2011. “Water Tracks and Permafrost in Taylor Valley, Antarctica: Extensive and Shallow Groundwater Connectivity in a Cold Desert Ecosystem.” Geological Society of America Bulletin 123 (11-12): 2295–2311. https://doi.org/10.1130/B30436.1.
Levy, Joseph S., Andrew G. Fountain, Kathy A. Welch, and W. Berry Lyons. 2012. “Hypersaline ‘Wet Patches’ in Taylor Valley, Antarctica.” Geophysical Research Letters 39 (5): n/a–. https://doi.org/10.1029/2012GL050898.
Northcott, Melissa L., Michael N. Gooseff, John E. Barrett, Lydia H. Zeglin, Cristina D. Takacs-Vesbach, and John Humphrey. 2009. “Hydrologic Characteristics of Lake- and Stream-Side Riparian Wetted Margins in the McMurdo Dry Valleys, Antarctica.” Hydrological Processes 23 (9): 1255–67. https://doi.org/10.1002/hyp.7262.
Outcalt, Samuel I., Frederick E. Nelson, and Kenneth M. Hinkel. 1990. “The Zero-Curtain Effect: Heat and Mass Transfer Across an Isothermal Region in Freezing Soil.” Water Resources Research 26 (7): 1509–16. https://doi.org/10.1029/WR026i007p01509.
Romanovsky, V. E., and T. E. Osterkamp. 2000. “Effects of Unfrozen Water on Heat and Mass Transport Processes in the Active Layer and Permafrost.” Permafrost and Periglacial Processes 11 (3): 219–39. https://doi.org/10.1002/1099-1530(200007/09)11:3{\textless}219::AID-PPP352{\textgreater}3.0.CO;2-7.
Wlostowski, A. N., M. N. Gooseff, and B. J. Adams. 2018. “Soil Moisture Controls the Thermal Habitat of Active Layer Soils in the McMurdo Dry Valleys, Antarctica.” Journal of Geophysical Research: Biogeosciences 123 (1): 46–59. https://doi.org/10.1002/2017JG004018.